Seal for electrochemical cell

Abstract

A seal and method of sealing for use in electrochemical cells and similar devices. A preformed seal assembly is produced by insert-molding a seal element about a cell cover plate. By preforming the seal element, a more effective seal geometry is produced. In particular, the seal element is formed with a low profile seal flange on the outer face of the cover plate. One benefit of this lower profile is to assist in increasing the effective capacity of the associated cell. Another benefit of the preformed seal element is that it is not necessary to grossly deform the seal element during cell assembly in order to capture the cover plate. This enables use of more desired seal materials such as amorphous polymers, particularly polysulfone. To improve the effectiveness of the seal, a seal flange and shoulder portions, between which the cover plate is captured, are each axially compressed to increase the leakage path and reduce cold flow of the seal element. The end of the cell container wall is bent inward to form a flange that is permanently biased against the seal flange to establish axial compression. The invention provides an improved method of cell assembly by reducing the seal element and cover plate to a single assembly prior to introduction in a cell. This simplifies cell fabrication and reduces waste due to improper assembly.

Dependencies are inferred from the claim text.